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221.
Effluent originating from distilleries contain large amount of dark brown coloured wastewater called molasses spent wash (MSW). This MSW is the unwanted residual liquid waste to dispose because of low pH, high temperature, dark brown colour, high ash content, unpleasant odour and high percentage of organic and inorganic matter. Dark brown colour of MSW is due to the presence of melanoidin pigment. It reduces sunlight penetration in rivers and lakes which in turn decrease both photosynthetic activity and dissolved oxygen concentration affecting aquatic life. So the disposal of this effluent is one of the critical environmental issues. A number of treatment processes have been employed for the distillery waste management. This review paper present an overview of the pollution problems caused by melanoidin and the technologies employed globally for its removal.  相似文献   
222.
An important role of oxidative stress for the development of vascular and neurological complications has encouraged us to undertake a study to assess the oxidative stress induced nerve conduction deficits among cigarette smokers. Eighteen regular male cigarette smokers and twenty nine male non-smokers were diagnosed for clinical neuro-physiological tests viz., motor and sensory nerve conduction velocity (MNCV and SNCV) and redox status. Significant depletion of reduced glutathione (GSH) level (p < 0.05) and significant increase in malondialdehyde (MDA) level (p < 0.01) was found in smokers compared to non-smokers. Motor and sensory nerve conduction velocity showed no significant difference among smokers compared to non-smokers. The present study shows that smoking can induce oxidative stress among smokers but could not exacerbate to nerve conduction deficits.  相似文献   
223.
Binding affinity of metanil yellow and its breakdown product p‐aminodiphenylamine to serum proteins has been studied employing chromatographic separation on Sephadex G‐200 and by paper and polyacrylamide gel electrophoresis. Metanil yellow has more affinity towards albumin than to globulins. The complexing is presumably through electrostatic forces. p‐Aminodiphenylamine on the other hand, preferably binds to globulin fractions of serum protein. However, a stable binding with BSA alone was also observed. The binding was quite stable and was accompanied by a shift in absorbance from 430 nm to 500 nm. Aspartic acid moiety of protein was found to be one of the units involved in the binding of p‐ADPA to proteins.  相似文献   
224.
    
Batch equilibrium and soil thin layer chromatography (TLC) techniques were used to investigate the influence of different volume fractions of organic cosolvents (acetone and methanol) on the adsorption and movement of carbaryl in four different types of Indian soils. L-shaped isotherms were obtained for both the cosolvent–water mixtures at all f s values and were in close agreement with the Freundlich equation. Higher adsorption was observed on F.R.I. soil (FSL) followed by Alampur soil (ASL), Kalai soil (KL), and Bhoran soil (BSL) at all f s values for both the cosolvent systems as was anticipated from the K and K D values. The K and K D values also confirmed that carbaryl adsorption was higher in methanol–water mixture than acetone–water mixture and decreased with increasing f s values. The frontal R f values obtained from soil TLC studies were inversely proportional to the K and K D values for both the cosolvent systems. The higher K and K D values and lower R f values in methanol–water mixtures relative to acetone–water mixtures for all the soils indicated that acetone had a greater potential for ground water contamination compared to methanol. The adsorption data were used to evaluate the cosolvent theory for describing adsorption of carbaryl in acetone–water and methanol–water mixtures. The aqueous phase partition coefficients, K DW (mol g?1), normalized with respect to f oc for carbaryl was evaluated by extrapolating f s → 0.  相似文献   
225.
A study was undertaken to explore the phytotoxicity of volatile essential oil from Eucalyptus citriodora Hook. against some weeds viz. Bidens pilosa, Amaranthus viridis, Rumex nepalensis, and Leucaena leucocephala in order to assess its herbicidal activity. Dose-response studies conducted under laboratory conditions revealed that eucalypt oils (in concentration ranging from 0.0012 to 0.06%) greatly suppress the germination and seedling height of test weeds. At 0.06% eucalypt oil concentration, none of the seed of test weeds germinated. Among the weed species tested, A. viridis was found to be the most sensitive and its germination was completed inhibited even at 0.03%. Not only the germination and seedling growth, even the chlorophyll content and respiratory activity in leaves of emerged seedlings were severely affected. In A. viridis chlorophyll content and respiratory activity were reduced by over 51% and 71%, respectively, even at a very low concentration of 0.06%. These results indicated an adverse effect of eucalypt oils on the photosynthetic and energy metabolism of the test weeds. A strong negative correlation was observed between the observed effect and the concentration of eucalypt oil. Based on the study, it can be concluded that oil from E. citriodora possess strong inhibitory potential against weeds that could be exploited for weed management.  相似文献   
226.
Commiphora mukul commonly known as Guggul is one of the oldest and commonly consumed herb for promoting heart and vascular health. Present study was undertaken to evaluate cardioprotective potential of Commiphora mukul against isoprenaline-induced myocardial necrosis in rats. Wistar albino rats were divided into three main groups: sham (saline only), isoprenaline control (saline and isoprenaline) and Commiphora mukul treated (Commiphora mukul and isoprenaline) groups. Commiphora mukul was administered in three doses 100, 200 and 400 mg kg(-1) p.o. for 30 days. On 29th and 30th day, the animals of isoprenaline control and Commiphora mukulpretreatment groups were administered isoprenaline (85 mg kg(-1); s.c.), consecutively at an interval of 24 hr. Isoprenaline administration produced a significant (p < 0.05) decrease in myocardial antioxidants; superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx), reduced glutathione (GSH), and myocyte injury marker enzymes creatine-phosphokinase-MB (CK-MB) and lactate dehydrogenase (LDH) along with enhanced lipid peroxidation; malondialdehyde (MDA) in heart. Commiphora mukul pretreatment reversed the isoprenaline-induced oxidative changes in rat myocardium by significant (p < 0.05) increase in SOD, CAT, GSHPx, GSH and reduction of MDA. In addition to improving myocardial antioxidant status, Commiphora mukul also prevented the leakage of LDH and CK-MB from heart. Further, histopathological examination showed the reduction of necrosis, edema and inflammation following Commiphora mukul pretreatment. Based on present findings, it is concluded that Commiphora mukul may be a potential preventive and therapeutic agent against the oxidative stress associated ischemic heart disease owing to antioxidant and antiperoxidative activity.  相似文献   
227.
Flavobacterium columnare (FC) and Myxobacterium sp. recorded persistently associated in fish hatchery and culture system of Himalayan and Sub - Himalayan regions were found to be pathogenic. The pH and salinity played a significant role on the pathogenicity of these potent pathogens in case of Clarias batrachus and Heteropneustes fossilis. LD50 value of FC was 10(4.5) CFU in both the fishes and those of Myxobacterium sp it was 10(6) CFU ml(-1) fish(-1). Fish challenged with F. columnare and Myxobacterium sp. (@ 0.2 ml fish(-1)) individually consisting 10(5-6) cfu ml(-1) exhibited explicit symptoms of columnaris disease and marked with ulceration and saddle back lesion on the dorsal side of body. Maximum reisolation of inoculated bacteria was recorded at pH 7.0 and 7.5 and at 0.0-0.5 (F. columnare) and 0.0-1.0% (Myxobacterium sp.) salinity. Foregoing results elucidated that F. columnare was more sensitive to salinity in comparison to Myxobacterium sp. and their pathogenicity significantly (p<0.05) depends on the salinity and pH that might be one of the physical factors to control their proliferation.  相似文献   
228.
Larvicidal potential of the extracts from different parts viz. green and red fruits, seeds, fruit without seeds, leaves and roots of Withania somnifera in different solvents was evaluated against larvae of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus, the important disease vectors prevalent in the semi-arid region. Experiments were carried out on late 3rd or early 4th instar larvae of these mosquitoes using standard WHO technique. 24 and 48 hr LC50 values along with their 95% confidence limits, regression equation, chi-square (chi2)/heterogeneity of the response have been determined by log probit regression analysis. The 24 hr LC50 values as observed for whole green fruits in water, methanol and petroleum ether were 350.9, 372.4, 576.9; 115.0, 197.1, 554.6; 154.9, 312.0, 1085.0 while corresponding values for red fruits were 473.5, 406.4,445.2; 94.7, 94.5, 1013.0; 241.8, 535.0, 893.3 mg l(-1) for An. stephensi, Ae. aegypti and Cx. quinquefasciatus respectively showing that methanol extracts were more effective against anophelines as compared to culicines when whole fruits were taken. The 24 hr LC50 values as observed for seeds in acetone, methanol and petroleum ether were 188.1, 777.5, 822.5; 245.5, 769.0, 1169.0; 140.3, 822.9, 778.4 and for fruit without seeds were 80.2, 97.6, 146.6; 88.4, 404.4, 1030.0; 30.0, 44.5, 54.2 mg l(-1) for the above mosquito species respectively showing that extract of fruit without seeds were most effective in petroleum ether followed by acetone and methanol extracts. However, experiments conducted with methanol extracts of leaves and roots of this plant species did not show any appreciable larvicidal activity and a 20-40% mortality was observed up to 500 mg l(-1) of the extracts. Overall larvae of anophelines were found more susceptible as compared to culicines to all the extracts tested. Petroleum ether extract of fruit without seeds was found most effective against all the mosquito species showing that active ingredient might be present in this part of the plant species. The study would be of great importance while planning vector control strategy based on alternative plant derived insecticides.  相似文献   
229.
In this study, we surveyed diversity in a range of local crops in the Lume and Gimbichu districts of Ethiopia, together with the knowledge of local people regarding crop uses, socio-economic importance, conservation, management and existing threats. Data were collected using semistructured interviews and participant observation. The study identified 28 farmers' varieties of 12 crop species. Among these, wheat (Triticum turgidum) and tef (Eragrostis tef) have high intra-specific diversity, with 9 and 6 varieties respectively. Self-seed supply or seed saving was the main (80?%) source of seeds for replanting. Agronomic performance (yield and pest resistance), market demand, nutritional and use diversity attributes of the crop varieties were highlighted as important criteria for making decisions regarding planting and maintenance. Over 74?% of the informants grow a combination of "improved" and farmers' varieties. Of the farmers' varieties, the most obvious decline and/or loss was reported for wheat varieties. Introduction of improved wheat varieties, pest infestation, shortage of land, low yield performance and climate variability were identified as the principal factors contributing to this loss or decline. Appropriate interventions for future conservation and sustainable use of farmers' varieties were suggested.  相似文献   
230.
Recognizing the array of effects that invasive alien species have, documenting their status from biodiversity rich regions has been much emphasized. Lack of such studies is a major limitation that hampers proper management of alien species. The present paper, therefore, documents the alien flora of the Indian Himalayan state of Himachal Pradesh (HP) based on data obtained from literature and herbarium records. The alien flora of HP comprises of 497 species belonging to 85 families. Majority of them belong to family Asteraceae (59 species), followed by Poaceae (47 species) and Fabaceae (43 species). Amongst the genera, Ipomoea (9 species), Eucalyptus and Euphorbia (7 species each) are the most predominant. Herbs constitute the majority (i.e., 73 %) of alien species and a large percentage of them (i.e., 22.94 %) have South America as their native region. Further, of the total alien species, 248 are intentional introductions and majority (31 % species) have been introduced for ornamental purposes. It was revealed that 34 % species have naturalized while 29 % species have become invasive. Today, in addition to human-disturbed landscapes, alien species have also been reported from dense forests. Himalaya being a biodiversity hotspot and HP being a bio-rich Himalayan state, it is hoped that this inventory and assessment of alien flora will help in designing informed management and monitoring strategies against problematic plant invasions in the state.  相似文献   
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